Diethyl sebacate was slightly irritant to the skin of rabbits. Skin sensitization has been reported in patients following topical application of preparations containing the sebacate, although an attempt to induce sensitization with a dilute solution was unsuccessful. Acute oral toxicity was low in rats and guinea-pigs treated orally and in rabbits treated dermally. Limited studies involving repeated oral administration to rats showed no toxic effects, although liver (peroxisomal) enzyme activity was increased in mice treated orally. Diethyl sebacate was not mutagenic in a very limited bacterial test.